setKey

Sets the Key data. The plaintext length of input key data is 16/24/32 bytes.
The data format is big-endian and right-aligned (the least significant bit is the least significant
bit of last byte). Input key data is copied into the internal representation.

Note:

If the key object implements the javacardx.crypto.KeyEncryption
interface and the Cipher object specified via setKeyCipher()
is not null, keyData is decrypted using the Cipher object.

getKey

Returns the Key data in plain text. The length of output key data is 16/24/32 bytes.
The data format is big-endian and right-aligned (the least significant bit is the least significant
bit of last byte).